时间:2021-07-01 10:21:17 帮助过:50人阅读
1、添加数据库路由分配文件
在项目文件夹里创建‘database_router’文件。将下面的代码复制到该文件里。
from django.conf import settings
DATABASE_MAPPING = settings.DATABASE_APPS_MAPPING
class DatabaseAppsRouter(object):
    """
    A router to control all database operations on models for different
    databases.
    In case an app is not set in settings.DATABASE_APPS_MAPPING, the router
    will fallback to the `default` database.
    Settings example:
    DATABASE_APPS_MAPPING = {'app1': 'db1', 'app2': 'db2'}
    """
    def db_for_read(self, model, **hints):
        """"Point all read operations to the specific database."""
        if model._meta.app_label in DATABASE_MAPPING:
            return DATABASE_MAPPING[model._meta.app_label]
        return None
    def db_for_write(self, model, **hints):
        """Point all write operations to the specific database."""
        if model._meta.app_label in DATABASE_MAPPING:
            return DATABASE_MAPPING[model._meta.app_label]
        return None
    def allow_relation(self, obj1, obj2, **hints):
        """Allow any relation between apps that use the same database."""
        db_obj1 = DATABASE_MAPPING.get(obj1._meta.app_label)
        db_obj2 = DATABASE_MAPPING.get(obj2._meta.app_label)
        if db_obj1 and db_obj2:
            if db_obj1 == db_obj2:
                return True
            else:
                return False
        return None
    def allow_syncdb(self, db, model):
        """Make sure that apps only appear in the related database.""
        if db in DATABASE_MAPPING.values():
            return DATABASE_MAPPING.get(model._meta.app_label) == db
        elif model._meta.app_label in DATABASE_MAPPING:
            return False
        return None
    def allow_migrate(self, db, app_label, model=None, **hints):
        """
        Make sure the auth app only appears in the 'auth_db'
        database.
        """
        if db in DATABASE_MAPPING.values():
            return DATABASE_MAPPING.get(app_label) == db
        elif app_label in DATABASE_MAPPING:
            return False
        return None2、在settings.py文件中配置多数据库
# Database
# https://docs.djangoproject.com/en/2.1/ref/settings/#databases
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'django_test',
        'HOST': '127.0.0.1',
        'USER': 'root',
        'PASSWORD': '123456',
        'PORT': '3306',
},
#配置第二个数据库
    'test': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'xsanjiaocheng',
        'HOST': '127.0.0.1',
        'USER': 'root',
        'PASSWORD': '123456',
        'PORT': '3306',
    }
}#设置数据库路由,将django_test改为你项目的名称。
DATABASE_ROUTERS = ['django_test.database_router.DatabaseAppsRouter']
#配置数据库与app的对应关系
DATABASE_APPS_MAPPING = {
    # example:
    # 'app_name':'database_name',
    # 'app01': 'test',
    'app01': 'default',
    'app02': 'test',
}3、在对应的app里的models.py文件里正常创建数据表即可(在创建表时尽量不要使用同样的表名)
app01中的models.py:
class django_test_1(models.Model):
    abc = models.CharField(max_length=20)
    class Meta:
        app_label='app01'
app02中的models.py:
class test_1(models.Model):
    tests= models.CharField(max_length=20)4、生成迁移文件
和以前一样:python manage.py makemigrations
5、迁移数据库
迁移时需指定数据库名
python manage.py migrate database=test
如果针对已创建好的数据库创建对应的models.py文件不用生成迁移文件,直接执行“python manage.py inspectdb > app02/models.py --database=test”的命令即可。
6、操作数据库
1)手动选择数据库
django_test_1.objects.using('default').create(abc='hdajh')2)自动选择数据库
和以前一样不加using()。
7、 配置urls.py
导入对应app的views.py的文件。最好命名个别名,或者给views.py文件重命名。
其他使用和以前一样。
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